Fibroblastic tumor of the premaxilla in two horses.

This research discusses two cases of horses suffering from unusual, fast-growing tumors in the premaxilla (front portion of the upper jaw) causing significant dental displacement and bone destruction. The study examines the diagnosis, treatment, and follow-up of these cases, with one horse successfully treated by surgical removal and cryosurgical therapy, and a second horse diagnosed postmortem with fibrosarcoma, a malignant bone cancer.

Case Study and Diagnosis

• The investigators report two cases of horses with fast-growing and invasive tumors located in the premaxilla, leading to severe displacement of the incisors and bone deterioration.
• For both horses, the tumors caused serious dental and skeletal complications, as noted through radiographic images. This disruption at the base of the tumors further indicated the aggressive nature of these growths.
• In the first horse, the tumor was surgically removed and the base where it had been growing was treated cryosurgically with liquid nitrogen, resulting in successful healing.
• The second horse was euthanized after an initial biopsy pointed towards osteogenic sarcoma, a severe type of bone cancer. The postmortem examination, however, revealed a fibrosarcoma, which is a malignant tumor derived from fibrous connective tissue.

Tumor Type and Treatment

• The tumor from the first horse was diagnosed as a benign fibroblastic tumor, possibly a fibroma, which originates from fibrous connective tissue and generally tends to be slow growing and non-invasive.
• The treatment involved surgical removal of the majority of the tumor along with cryosurgery, a technique that uses extreme cold to destroy abnormal tissues. This was achieved through three freeze-thaw cycles using liquid nitrogen. The healing took place by secondary intention, a process where a wound is allowed to heal on its own without surgical closure.
• Four years after the procedure, there has been no sign of the tumor’s recurrence, indicating that the treatment was successful.

Osteogenic Sarcoma vs. Fibrosarcoma

• The second horse was initially suspected to have osteogenic sarcoma based on a biopsy but had to be euthanized due to the severity of the situation.
• The postmortem diagnosis revealed fibrosarcoma without metastasis, suggesting that while the tumor was malignant and aggressive, it had not spread to other parts of the body before the horse was euthanized.

Conclusion

• This study highlights the importance of accurate diagnosis and treatment of unusual tumors in horses, as misdiagnosis can lead to suboptimal treatment plans and outcomes.
• Further, it demonstrates the effectiveness of cryosurgery in dealing with certain types of benign tumors, as seen in the case of the horse with the fibroblastic tumor.